Thanks Darien from /freenode #php for the following example (a little bit changed).
It just prints the 6th character of $string.
You can replace the digits by the same in japanese, chinese or whatever language to make a test, it works perfect.
<?php
mb_internal_encoding("UTF-8");
$string = "0123456789";
$mystring = mb_substr($string,5,1);
echo $mystring;
?>
(I couldn't replace 0123456789 by chinese numbers for example here, because it's automatically converted into latin digits on this website, look :
零一二三四
五六七八九)
gilv
